Uncooperative patients suspected of acute stroke ineligible for prehospital stroke screening test by emergency medical service providers: final hospital diagnoses and characteristics

Han Sol,Song Sung Wook,Hong Hansol,김우정,강영준,Park Chang Bae,Kang Jeong Ho,Bu Ji Hwan,이성근,Ko Seo Young,이수훈,Kang Chul-Hoo 대한응급의학회 2023 Clinical and Experimental Emergency Medicine Vol.10 No.2

Objective: This study investigated the hospital diagnoses and characteristics of uncooperative prehospital patients suspected of acute stroke who could not undergo a prehospital stroke screening test (PHSST). Methods: This retrospective observational study was conducted at a single academic hospital with a regional stroke center. We analyzed three scenario-based prehospital stroke screening performances using the final hospital diagnoses: (1) a conservative approach only in patients who underwent the PHSST, (2) a real-world approach that considered all uncooperative patients as screening positive, and (3) a contrapositive approach that all uncooperative patients were considered as negative. Results: Of the 2,836 emergency medical services (EMS)-transported adult patients who met the prehospital criteria for suspicion of acute stroke, 486 (17.1%) were uncooperative, and 570 (20.1%) had a confirmed final diagnosis of acute stroke. The diagnosis in the uncooperative group did not differ from that in the cooperative group (22.0% vs. 19.7%, P=0.246). The diagnostic performances of the PHSST in the conservative approach were as follows: 79.5% sensitivity (95% confidence interval [CI], 75.5%–83.1%), 90.2% specificity (95% CI, 88.8%–91.6%), and 0.849 area under the receiver operating characteristic curve (AUC; 95% CI, 0.829–0.868). The sensitivity and specificity were 83.3% (95% CI, 80.0%–86.3%) and 75.2% (95% CI, 73.3%–76.9%), respectively, in the real-world approach and 64.6% (95% CI, 60.5%–68.5%) and 91.9% (95% CI, 90.7%–93.0%), respectively, in the contrapositive approach. No significant difference was evident in the AUC between the real-world approach and the contrapositive approach (0.792 [95% CI, 0.775–0.810] vs. 0.782 [95% CI, 0.762–0.803], P>0.05). Conclusion: We found overestimation (false positive) and underestimation (false negative) in the uncooperative group depending on the scenario-based EMS stroke screening policy for uncooperative prehospital patients suspected of acute stroke.

The Study on Effect and Necessity of Manual Therapy Force Scale Training

Hansol, Park 보완대체의학연구소 2016 Research Journal of Complementary and Alternative Vol.- No.7

The first reported hepatitis E outbreak in a food manufacturing factory: Korea, 2022

Hansol Yeom,Soonryu Seo,Youngsil Yoon,Jaeeun Lee,Myung-Guk Han,Lee Deog-Yong,Sun-Whan Park,Song A Park,Jeong Sook-Hyang,Jin Gwack 질병관리본부 2023 Osong Public Health and Research Persptectives Vol.14 No.1

Objectives: On February 16, 2022, 12 cases of hepatitis E virus (HEV) infection were reported in a food manufacturing factory in Korea. The aim of this study was to identify additional cases and to determine the source of this HEV outbreak. Methods: This study was an in-depth investigation of 12 HEV immunoglobulin M (IgM)-positive cases and their demographic, clinical, and epidemiological characteristics. On-site specimens were collected from the environment and from humans, and a follow-up investigation was conducted 2 to 3 months after the outbreak. Results: Among 80 production workers in the factory, 12 (15.0%) had acute HEV infection, all of whom were asymptomatic. The follow-up investigation showed that 3 cases were HEV IgM-positive, while 6 were HEV IgG-positive. HEV genes were not detected in the HEV IgM-positive specimens. HEV genes were not detected in the food products or environmental specimens collected on-site. HEV was presumed to be the causative pathogen. However, it could not be confirmed that the source of infection was common consumption inside the factory. Conclusion: This was the first domestic case of an HEV infection outbreak in a food manufacturing factory in Korea. Our results provide information for the future control of outbreaks and for the preparation of measures to prevent domestic outbreaks of HEV infection.

Severe Phenotypic Presentation of RPGR -associated X-linked Retinitis Pigmentosa in Female Carriers: Two Case Reports

Hansol Park,Sungsoon Hwang,Sang Jin Kim 대한안과학회 2024 Korean Journal of Ophthalmology Vol.38 No.2

Universal, colorimetric microRNA detection strategy based on target-catalyzed toehold-mediated strand displacement reaction

Park, Yeonkyung,Lee, Chang Yeol,Kang, Shinyoung,Kim, Hansol,Park, Ki Soo,Park, Hyun Gyu IOP 2018 Nanotechnology Vol.29 No.8

<P>In this work, we developed a novel, label-free, and enzyme-free strategy for the colorimetric detection of microRNA (miRNA), which relies on a target-catalyzed toehold-mediated strand displacement (TMSD) reaction. The system employs a detection probe that specifically binds to the target miRNA and sequentially releases a catalyst strand (CS) intended to trigger the subsequent TMSD reaction. Thus, the presence of target miRNA releases the CS that mediates the formation of an active G-quadruplex DNAzyme which is initially caged and inactivated by a blocker strand. In addition, a fuel strand that is supplemented for the recycling of the CS promotes another TMSD reaction, consequently generating a large number of active G-quadruplex DNAzymes. As a result, a distinct colorimetric signal is produced by the ABTS oxidation promoted by the peroxidase mimicking activity of the released G-quadruplex DNAzymes. Based on this novel strategy, we successfully detected miR-141, a promising biomarker for human prostate cancer, with high selectivity. The diagnostic capability of this system was also demonstrated by reliably determining target miR-141 in human serum, showing its great potential towards real clinical applications. Importantly, the proposed approach is composed of separate target recognition and signal transduction modules. Thus, it could be extended to analyze different target miRNAs by simply redesigning the detection probe while keeping the same signal transduction module as a universal signal amplification unit, which was successfully demonstrated by analyzing another target miRNA, let-7d.</P>

Effective subgroup method employing macro level grid optimization for LWR applications

Park, Hansol,Joo, Han Gyu Elsevier 2019 Annals of nuclear energy Vol.129 No.-

<P><B>Abstract</B></P> <P>The Macro Level Grid scheme for the efficient application of the subgroup method is presented, that employs the number density consideration factor and the temperature consideration factor for the treatment of non-uniform number densities and temperature distributions in a core. This scheme provides the efficient resonance treatment in direct whole core calculations of power reactors that involve thermal feedback and isotopic depletion. The new method solves the subgroup fixed source problem only 8 times per energy group with 8 macroscopic subgroup levels, regardless of the number of resonance isotopes in the problem of interest. The escape cross section of each isotope is obtained by interpolation using the pre-calculated ones at the specified macroscopic subgroup levels. This scheme turns out to be superior to the conventional scheme in terms of computing time and accuracy. More than 30% of the computing time for fixed source problems is saved compared to the conventional one with negligible reactivity errors of about a few pcm, whereas the conventional one has consistent reactivity errors of about +60 ∼ +150 pcm for typical pin-cell problems in a light water reactor. Moreover, it turns out that the new method provides high accuracy not only for very heterogeneous uranium dioxide and mixed oxide pin-cell checkerboard problems, but also for the depletion calculation of a multi-assembly problem involving hot full power thermal feedback with significantly shortened times.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Macroscopic escape XSs are computed at common grid, called macro level grid. </LI> <LI> Isotopewise escape XSs are interpolated from the macro level grid. </LI> <LI> Optimum number of subgroup levels for the grid turns out to be 8 for LWR geometry. </LI> <LI> Total number of SGFSPs are fixed regardless of number of isotopes and their levels. </LI> <LI> Same accuracy as original isotopewise SGFSP scheme and reduced computing time. </LI> <LI> Verified at 3 by 3 assembly checkerboard with HFP thermal feedback. </LI> </UL> </P>

Thermal stability and degradation kinetics of polyphenols and polyphenylenediamines enzymatically synthesized by horseradish peroxidase

Hansol Park,권오열,류근갑 한국화학공학회 2015 Korean Journal of Chemical Engineering Vol.32 No.9

Various substituted phenols and phenylenediamines were enzymatically polymerized by horseradish peroxidase in 80% (v/v) organic solvents-aqueous buffer (100 mM sodium acetate, pH 5) mixtures with H2O2 as the oxidant. The thermal stability of the polymers was investigated by thermogravimetric analysis (TGA) and represented by the char yield (wt% of the initial polymer mass) after being heated at 800 oC. Poly(p-phenylphenol) had the highest thermal stability among the synthesized polymers with a char yield of 47 wt%. The polymers containing amino groups such as poly(p-aminophenol) and polyphenylenediamines were also shown to possess high thermal stabilities. The activation energies for the thermal degradation of the polymers determined by derivative thermogravimetric analysis (DTG) using Horowitz-Metzger’s pseudo-first-order kinetics were in the range between 23-65 kJ/mol and comparable to those of the chemically synthesized polymers. Dynamic structural changes of the enzymatically synthesized polymers upon heating were studied by differential scanning calorimetry (DSC). The DSC curves of poly(p-phenylphenol) showed a broad exothermic peaks between 150-250 oC, indicating that the polymer undergoes complex structural transitions in the temperature range. On the other hand, the DSC curves of the poly(p-aminophenol) and the poly(p-phenylenediamine) which contain amino groups showed strong sharp endothermic peaks near 150 oC, implying that these polymers possess homogeneous oriented structures which undergo a concerted structural disintegration upon heating.

Experimental Evaluation of Unmanned Aerial Vehicle System Software Based on the TMO Model

Hansol Park,Doo-Hyun Kim,Jung-Guk Kim,Chun-Hyon Chang 한국정보과학회 2008 Journal of Computing Science and Engineering Vol.2 No.4

Over the past few decades, a considerable number of studies have been conducted on the technologies to build an UAV (Unmanned Aerial Vehicle) control system. Today, focus in research has moved from a standalone control system towards a network-centric control system for multiple UAV systems. Enabling the design of such complex systems in easily understandable forms that are amenable to rigorous analysis is a highly desirable goal. In this paper, we discuss our experimental evaluation of the Time-triggered Message-triggered Object (TMO) structuring scheme in the design of the UAV control system. The TMO scheme enables high-level structuring together with design-time guaranteeing of accurate timings of various critical control actions with significantly smaller efforts than those required when using lowerlevel structuring schemes based on direct programming of threads, UDP invocations, etc. Our system was validated by use of environment simulator developed based on an open source flight simulator named FlightGear. The TMO-structured UAV control software running on a small computing platform was easily connected to a simulator of the surroundings of the control system, i.e., the rest of the UAV and the flight environment. Positive experiences in both the TMO-structured design and the validation are discussed along with potentials for future expansion in this paper.

Understanding DFT Calculations of Weak Interactions: Density-Corrected Density Functional Theory

Park, Hansol,Kim, Yeil,Sim, Eunji Korean Chemical Society 2019 대한화학회지 Vol.63 No.1

In this work, we discuss where the failure of Kohn-Sham Density Functional Theory (DFT) occurs in weak interactions. We have adopted density-corrected density functional calculations and dispersion correction separately to find out whether the failure is due to density-driven error or functional error. The results of Benzene Ar complex, one of the most common examples of van der Waals interactions, show that DFT calculations of van der Waals interaction suffer from functional error, rather than density-driven error. In addition, errors in DFT calculations of the S22 dataset, which contains small to relatively large (30 atoms) complexes with non-covalent interactions, are governed by functional errors.

FeOF ellipsoidal nanoparticles anchored on reduced graphene oxides as a cathode material for sodium-ion batteries

Park, Miji,Shim, Jae-Hyun,Kim, Hanah,Park, Hansol,Kim, Namyeong,Kim, Jongsik Elsevier 2018 Journal of Power Sources Vol.396 No.-

<P><B>Abstract</B></P> <P>FeOF/reduced graphene oxide (r-GO) nanocomposites are synthesized with approximately 8 and 13 wt% r-GO. The FeOF nanoparticles are fabricated using FeSiF<SUB>6</SUB>⋅6H<SUB>2</SUB>O as a precursor through solvothermal treatment with 1-propanol. This method provides a more reliable and facile wet-chemical route to synthesize phase-pure FeOF without FeF<SUB>2</SUB> and Fe<SUB>2</SUB>O<SUB>3</SUB> impurities, as compared to the annealing process in air. The FeF<SUB>2</SUB> phase is formed as an intermediate during the synthetic process. The prepared FeOF/r-GO sample with 13 wt% r-GO (FeG20) exhibits improved discharge capacity, cycling stability, and rate performance as a cathode material in sodium-ion batteries, compared to the bare FeOF at 1.2–4.0 V. The enhanced electrochemical properties for sodium-ion storage are mainly attributed to the size-controlled FeOF nanoparticles and their intimate contact with the conductive r-GO matrix.</P> <P><B>Highlights</B></P> <P> <UL> <LI> Ellipsoidal FeOF nanoparticles anchored on r-GO were fabricated in a mild condition. </LI> <LI> The particle size of FeOF was decreased with the r-GO contents in the FeOF/r-GO composites. </LI> <LI> The FeOF/r-GO composites show superior electrochemical performances to those of bare FeOF. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>